Mechanical time fuse mechanism for projectiles



G. HOENGER MECHANICAL TIME FUSE MECHANISM FOR PROJECTILES Dec. 29, 1953 4 Sheets-Sheet 1 Filed April 23 1951 5 Gucczo Hoenyeh Y g Att G. HOENGER Dec. 29, 1953 MECHANICAL TIME FUSE MECHANISM FOR PROJECTILES 4 Sheets-Sheet 2 Filed April 25 1951 G. HOENGER Dec. 29, 1953 MECHANICAL TIME FUSE MECHANISM FOR PROJECTILES G. HOENGER Dec. 29, 1953 2,664,046 MECHANICAL TIME FUSE MECHANISM FOR PROJECTILES 4 Sheets-Sheet 4 Filed April 23, 1951 i Patented Dec. 29, 1953 was MECHANICAL TIME FUSE MECHANISM FOR PROJECTILES Guido Hoenger, Zuchwil, Switzerland, assignor to Melina S. A., Binningen, Switzerland, a corporation of Switzerland Application April 23, 1951, Serial No. 222,343

Claims priority, application Switzerland July 7, 1950 Claims. 2

This invention relates to projectile fuses and more particularly has reference to a mechanical time fuse mechanism and its controls.

To satisfy the continually increasing requirements for precision in artillery fire, there are needed more and more, in mechanical time fuses or combined time and percussion fuses, mechanisms which can be set for 60 seconds and more while guaranteeing the smallest possible var-iation from the maximum timing, in order to avoid inadmissible dispersion in firing,

Three general types of mechanical time fuses are known, as follows:

1. The type in which the setting is made over somewhat less than one turn. In this case, the angle of setting read on the fuse is too small to avoid certain errors, the result of which is excessive dispersion on firing.

2. The type in which the setting is made over a plurality of turns, the setting mechanism turning through exactly the same angle as the fuse, but the member controlling the release of the striker or detonator pin is displaced angularly only through an angle less than 360, by means of a reduction gear. This construction has the disadvantage that the angular variations in the displacement in this control member, due to play in the reduction gear, results in a dispersion on firing which may exceed admissible limits.

3. The type in which the setting is made over a plurality of turns as above, but in which the member controlling the release of the striker or detonator pin turns through the same angle as the setting mechanism. Therefore, in setting the timing of the fuse, this member rotates through the same angle as the angle of setting, which results in high precision. Constructions of this kind, however, always have the disadvantage of being more complicated than the others and, therefore, are more expensive.

A construction of this kind is known in which the member controlling the release of the detonator pin comprises a bell-like member with a fiat base on one of the faces of which are formed a plurality of turns of an Archimedian spiral. This spiral engages a tooth or spur on a slotted bolt which undergoes displacement in radial direction when the bell-like member is turned. The striker or detonator pin has its point extending into the slot and has a collar which bears against the side of the slotted bolt. The spring for the striker or detonator pin urges the same strongly against the slotted bolt which due to friction retards its movement over the spiral of the bell-like member. This friction has a substantial influence on the proper operation of the mechanism.

The present invention has for its primary object to provide a mechanical time fuse mechanism, with or without instantaneous precussion, which is set by rotating the setting member through a plurality of turns, and in which the member controlling the release of the striker, driven in rotation by the clock-work movement from the time of firing, is displaced angularly upon setting through the same angle as the said movement.

This construction differs from the known construction by the simplicity of the member controlling the release of the striker or detonating pin, which comprises a guide in the form of a single turn of a spiral, this guide being normally in engagement with an intermediate oscillating bolt controlling the release of a striker bolt and cooperating with a centrifugal bolt for retaining the member which controls the release. The guide in form of a spiral may extend through an angle of less than 360.

In the drawings there is illustrated by way of example one constructional embodiment of the invention providing for a setting which can be effected over three turns.

In these drawings, Fig. 1 is an elevational view partly in section of the mechanism;

Fig. 2 is a sectional view taken on line II-II of Fig. 1 showing the position of different parts at rest, that is, in the starting position of setting; and

Figs. 3 and 4 are similar sectional views showing the position of the parts respectively at the end of the three turns of setting, and after the release of the striker.

Referring to Figs. 1 and 2., the member controlling the release of the striker 6 comprises a bell-shaped member 8 which can make three turns with respect to the frame plate 20, and has a guide rib 1 in the form of an Archimedian spiral with its beginning at la and its end at lb. This spiral rib extends through an angle less than 360 so as to leave a gap between its two ends. An oscillating control bolt 9, referred to herein as an intermediate bolt has a portion 2 positioned to cooperate with the spiral guide 1. Bolt 9 is pivoted at one of its ends about pivot I on the plate 20 and its aforesaid portion 2 extending transversely of the spiral guide I has three teeth 9a, each of a curvature substantially similar to that of the guide thread 1 and adapted to engage with the latter.

The teeth 9a are spaced from each other by a distance corresponding to the pitch of the spiral rib 1. They extend over the portion 2 of the bolt 9 through a length greater than the free space between the ends of the spiral rib 1, so that one of them can still be in engagement with the end 117 while the rest is already in engagement with the other end 1a of the guide rib I. The end of the bolt portion 2 has a nose 9b of such dimensions that it can pass freely between the ends in and lb of the spiral rib 1.

The bolt 9 also has a nose 21 with a circular arcuate surface having the axis of the pivot l as its center of curvature.

The frame plate 20 also has mounted thereon a striker engaging bolt [8 pivoted at 3 and having a boss 18a on which bears the flange of the striker 6. This bolt l8 also has a nose 22 cooperating with the nose 2! of the intermediate bolt 9.

The plate 293 also carries a bolt ll pivoted at 4 and designated as a centrifugal bolt. Its free end or point He engages a notch 80 in the bell-like member 8 in position of rest. It also has a projection 23 cooperating with the striker engaging bolt l8 and also with the nose 2| of the intermediate bolt e.

The three bolts 9, i1 and [8 are under the action of springs 9, H and I8 respectively. The spring H of the centrifugal bolt ll tends to urge it inwardly towards the center while the springs 9, I8 of the intermediate bolt 9 and of the striker engaging bolt I8 respectively tend to urge them outwardly.

The operation of this mechanism is as follows:

When the mechanism is at rest, in the zero position shown in Fig. 2, spring ll urges the centrigual bolt ll inwardly about its pivot 4 and the point lla engages the notch 8c of the release bell-like member 8, holding the latter in the position shown. The intermediate bolt 9 is held by 4:

its nose 92) against the end 1a of the spiral guide rib I of the release bell-like member 8. The arcuate nose 2i of the bolt 9 retains the nose 22 of the striker engaging bolt H8. The latter is also held in its safety or locked position by the projection 23 of the centrifugal bolt 11, which eliminates any risk of premature percussion, as by vibration or breakage of any member.

To effect setting, one of the parts A and B of the mechanism, Fig. 1, is rotated relatively to the other.

At the beginning of the setting, the notch 80 in the release bell-like member 8 which rotates with part A in a clockwise direction as shown in Figs. 2-4 during setting leaves the point or pawl [1a of the centrifugal bolt H.

Relative rotation of the parts A and B results in the intermediate bolt 9 being drawn inwardly by the action of the spiral guide rib 1 of the release bell-like member 8 which on turning inserts its end la successively into the gaps between the teeth 9a of the bolt 9. As the center of pivoting of bolt 9 corresponds to the center of curvature of the arcuate nose 2|, the latter slides during the setting on the nose 22 of the striker locking bolt I8. Therefore, bolt I8 is firmly held during the entire setting, and this condition continues while the clock-work movement is running and the nose 2| of the bolt 9 is sliding outwardly. This nose 2| also remains in engagement with the projection 23 as long as a tooth 9a is in engagement with the spiral guide 1. During the setting of the fuse (rotation of member 8 to draw bolt 9 inwardly), the nose 2] of the bolt 9 has .a second function of acting on the projection 23 to I push the centrifugal bolt l1 outwardly in such a manner that if the clockwork movement is started from rest, the point Il'a of the centrifugal bolt 11 urged inwardly by its spring I? cannot stop rotation of the release bell-like member 8 by engaging its notch 80 until the end of the last turn. After the setting is finished, for example, after three complete turns, as shown in Fig. 3, the fuse is ready for firing. Upon firing, the clockwork movement is automatically started. The barrel spring 5, Fig. 1, which was wound during setting, causes the barrel shaft [5 to turn which drives the member regulating the clock-work movement and also the release bell-like member 8. Centrifugal force overcomes the effect of the spring H and urges the centrifugal bolt I! outwardly against the wall of its housing. The release bell-like member is thus no longer held by the point Ha at the end of the last turn (Fig. 2).

On the other hand, the projection 23 no longer prevents the striker bolt l8 from issuing at the instant it is released by the nose 2! of the bolt 9. The release of the striker which causes the detonation is effected in the following manner with reference to Fig. 4: The release bell-like member 8 on arriving at the end of the last turn, brings the intermediate bolt 9 into the position shown in Fig. 2. The bell-like member 8 continues its travel'which results in the release of bolt 9 causing its nose 9b to pass between the ends 1a and 1b of the spiral guide rib l. The bolt 9 is then urged against the outer wall of its housing b its spring 9' and centrifugal force.

The arcuate nose 2| having effected the same movement as the bolt 9 abruptly deprives the nose 22 of support and frees the bolt l8. The bolt I8 is then urged outwardly by its spring and centrifugal force to a position freeing the striker 6.

, Under the action of the spring M, as the striker 6 is suddenly deprived of support, Fig. 1, it is impelled against the cap, not shown in the drawing.

The mechanism described and illustrated is constructed for a setting of three turns. It can be regulated for a time of 20, 25, 30 seconds, etc., per turn. If it is regulated for 25 seconds per turn, the setting is '75 seconds for three turns. The angle of setting on the fuse, which is equal to the angle of displacement of the release bell-like member, is for each second of time:

3.360 1080 3.25 sec. sec.

which permits great precision.

Having described my invention, I claim:

1. Amechamcal time fuse mechanism for projectiles comprising a striker for detonating the fuse, a clockwork mechanism, a rotary member driven by said clockworkmechanism through a plurality of revolutions, a guide member on said rotary member in the form of a single spiral, a striker locking bolt =movab1e to and from striker locking position, a centrifugal bolt engageable with said rotary member for retaining itagainst rotation, and an intermediate pivoted bolt .havmg means engageable with said spiral guide for shifting said intermediate bolt in one direction upon rotation in one direction-for setting the fuse and for shifting said intermediate boltin the 'opposite direction upon driving of the rotary member in the opposite direction by the clockwork mechanism, said intermediate bolt having a port1on engaging the centrifugal bolt for shifting the centrifugal bolt to a position to release the rotary member upon setting the fuse and also engaging the .striker locking bolt for controlling release movement of said striker bolt.

2. A mechanism according to claim 1 in which said spiral guide consists of a spiral rib.

3. A mechanical time fuse mechanism for projectiles comprising a striker for detonating the fuse, a clockwork mechanism, a rotary member driven by said clockwork mechanism through a plurality of revolutions, a guide member on said rotary member in the form of a single spiral, a striker locking bolt movable to and from striker locking position, a centrifugal bolt engageable with said rotary member for retaining it against rotation, and an intermediate pivoted bolt having a portion disposed transversely to the spiral guide, a nose on the free end of said portion of dimensions capable of freely passing between the ends of said guide, a plurality of teeth on said portion having a curvature substantially the same as that of the spiral guide and spaced apart a distance equal to the pitch of said spiral guide and extending over length greater than the distance between the ends of the spiral guide, said teeth and spiral guide cooperating for shifting said intermediate bolt i one direction upon rotation in one direction for setting the fuse and for shifting said intermediate bolt in the opposite direction upon driving of the rotary member in the opposite direction by the clockwork mechanism, said intermediate bolt cooperating with the centrifugal bolt and controlling release movement of said striker bolt.

4. A mechanical time fuse mechanism for projectiles comprising a striker for detonating the fuse, clockwork mechanism, a rotar member driven by said clockwork mechanism through a plurality of revolutions, a guide member on said posite direction upon driving of the rotary memher in the opposite direction by the clockwork mechanism, a nose on the striker bolt, an arouate nose on the intermediate bolt concentric with the pivot axis of said intermediate bolt, and positioned to engage the nose of the striker bolt and prevent release movement of the striker bolt as long as the intermediate bolt engages the spiral guide, and means on the centrifugal bolt cooperating with said arcuate nose for shifting the centrifugal bolt out of engagement with the rotary member upon setting the fuse.

5. A mechanical time fuse mechanism for projectiles comprising a striker for detonating the fuse, a clockwork mechanism, a rotary member driven by said clockwork mechanism through a plurality of revolutions, a guide member on said rotary member in the form of a single spiral, a striker locking bolt movable to and from striker locking position, said rotary member having a notch in a peripheral portion thereof, a centrifugal bolt having a portion engageable in said notch to retain said rotary member against rotation, and an intermediate pivoted bolt having means engageable with said spiral guide for shifting said intermediate bolt in one direction upon rotation in one direction for setting the fuse and for shifting said intermediate bolt in the opposite direction upon driving of the rotary member in the opposite direction by the clockwork mechanism, said intermediate bolt having portion engaging the centrifugal bolt for shifting the centrifugal bolt to a position to release the rotary member upon setting the fuse and also engaging the striker locking bolt for controlling release movement of said striker bolt.

6. A mechanical time fuse mechanism for projectiles comprising a striker for detonating the fuse, a clockwork mechanism, a rotary member driven by said clockwork mechanism through a plurality of revolutions, a guide member on said rotary member in the form of a single spiral, a striker locking bolt movable to and from striker locking position, a centrifugal bolt engageable with said rotary member for retaining it against rotation, and an intermediate pivoted bolt having means engageable with said spiral guide for shifting said intermediate bolt in one direction upon rotation in one direction for setting the fuse and for shifting said intermediate bolt in the opposite direction upon driving of the rotary member in the opposite direction by the clockwork mechanism, and a nose on the intermediate bolt positioned to push the centrifugal bolt outwards by setting the fuse, the centrifugal bolt releasing the rotary member to allow a plurality of revolutions of said rotary member.

'7. A mechanical time fuse mechanism for projectiles comprising a striker for detonating the fuse, aclockwork mechanism, a rotary member driven by said clockwork mechanism through a plurality of revolutions, a guide member on said rotary member in the form of a single spiral, a striker locking bolt movable to and from striker locking position, a centrifugal bolt engageable with said rotary member for retaining it against rotation, and an intermediate pivoted bolt having means engageable with said spiral guide for shifting said intermediate bolt in one direction upon rotation in one direction for setting the fuse and for shifting said intermediate bolt in the opposite direction upon driving of the rotary member in the opposite direction by the clockwork mechanism, said intermediate bolt having a nose cooperating with the centrifugal bolt to shift it to releasing position and controlling release movement of said striker bolt, said centrifugal bolt having a portion operable when the centrifugal bolt is in its inner position to block release movement of the striker bolt, and operable in its outer position to free the striker bolt for release movement.

8. A mechanical time fuse mechanism for projectiles comprising a fuse body, a striker, a rotary member having its axis parallel to the axis of the fuse and rotatable through a plurality of revolutions, a driven spring having one end connected to the fuse body and the other end connected to a rotary part coupled with said rotary member whereby upon rotating the rotary member in one direction the spring will be wound for subsequently rotatably driving the rotary member in the opposite direction, a clockwork mechanism coupled with said rotary member for controlling the rate of rotation of the same when driven by said spring, a striker locking bolt pivotally mounted on said body about an axis parallel to the fuse axis for movement to and from locking position, a spring urging the striker bolt outwardly from the axis of the fuse to release position, a guide member on the rotary member in the form of a single spiral rib and having a free space between the ends thereof, a centrifugal bolt pivotally mounted on said body about an axis parallel to the fuse axis, a spring urging said centrifugal bolt inwardly, an intermediate bolt pivotally mounted ansaid'bodyfor movement about an axis parto the pitch of said spiral guide and extending;

over a. length greater than .thevdistance between the ends ofthe spiral guide; said teeth and spiral guide cooperating for shifting the, intermediate bolt inwardly upon rotating the rotary member to wind thelspring and for shifting the intermediatebolt outwardly upon the rotary member being driven by the spring, and a spring urging the intermediate bolt outwardly, said intermediate bolt cooperating with the centrifugal bolt and controlling release movement of'said striker bolt.

9. A mechanical time fuse mechanism for projectiles comprising alfuse body, a striker, a rotary member having its axis parallel to the axis of the fuse and rotatable through a plurality, of

revolutions, a driven spring-having one end con- Q nected to the fuse body andthe other, end connected to. a rotary part coupled with said rotary member whereby upon rotating the rotary member in on direction thezspring will berwound for subsequently.rotatablydriving the rotary member in theopposite direction, a clockwork mechanism coupled with said rotary member for controlling the rate of rotation of the same when driven by said spring, a striker locking bolt pivotally mounted on said body about van axis parallel to the fuse axis for movement to. and from looking position, a spring urgingthe striker bolt outwardly from the axis of the fuse to release position, a guide member on the rotary member in theform of a single spiralrib extending through an angle of less than 360 and having a free space between the ends thereof, a centrifugal bolt pivotally mounted on said body about an axis parallel to the fuse axis, a spring urging said centrifugal boltinwardly, an intermediate bolt pivsaid guide, a plurality of teeth on said portion,

havinga curvature substantially the same as, that 8 of the spiral guide and spacedaparta distance equal to the pitch of said spiral guide and extend,- ing over a length greaterthan the distance between the ends of the spiral guide, said teeth and spiral guide cooperating for shifting the intermediate bolt inwardly upon rotating the rotary member to wind the spring and for shifting the intermediate bolt outwardly upon the rotary member being driven by the spring, and a spring urging the intermediate bolt outwardly, a. nose on the strikerv bolt, an arcuate nose on the intermediate bolt concentric with the pivot axis of said intermediate bolt, and positioned to engage the nose of the striker bolt and prevent release movement of the striker bolt as long as the intermediate bolt engages the spiral guide, and means ,on the centrifugal bolt cooperating with said arcuate nose.

10. A mechanical time fuse mechanism for projectiles comprising a striker for detonating the fuse, a clockwork mechanism, a rotary member driven by said clockwork mechanism through a plurality of revolutions, a guide member on said rotary member in the form of a single spiral extending through an angle of less than 360, a striker locking bolt movable to and from striker locking position, a centrifugal bolt engageable with said rotary member for retaining it against rotation, and an intermediate pivoted bo-lt having means engageable with said spiral guid for shifting said intermediate bolt in one direction upon rotation in one direction for setting the fuse and for shifting said intermediate bolt in the opposite direction upon driving of the rotary member inthe opposite direction by the clockworkmechanism, said intermediate bolt having a portion engaging the centrifugal bolt for shifting the centrifugal bolt to a position to release the rotary member upon setting the fuse and also engaging the striker locking bolt for controlling release movement of said striker bolt.

GUIDO HOENGER.

References Cit-ed in the file of this patent FOREIGN PATENTS Number Country Date 266,030 Switzerland Apr. 1, 1950 265,588 Great Britain May 2, 1928 511,249 France Sept. 22, 1920 842,692 France Mar. 13, 1939 

